deltaH
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Amide vs ester selectivity
If a molecule has both a primary amine and secondary hydroxyl functional groups and you form the formate salt of it, upon strong heating, would you
form predominantly the formamide or formate ester or mixture of both without a major dominance of one over the other?
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deltaH
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I have just read on wikipedia that amides may be formed by the reaction of an amine with an ester, something called ester aminolysis, so I guess I can
answer my own question, at least superficially. So if you have both a secondary hydroxyl group and amine group on your molecule and use one equivalent
of acid, ultimately, forming the amide should dominate?
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Etaoin Shrdlu
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Likely would. Amides are more stable than esters because the lone pair on nitrogen delocalizes very well into the pi system, making the carbon less
electrophilic.
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deltaH
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Quote: Originally posted by Etaoin Shrdlu  | | Likely would. Amides are more stable than esters because the lone pair on nitrogen delocalizes very well into the pi system, making the carbon less
electrophilic. |
Nice explanation Etaoin Shrdlu, makes a lot of sense, thanks!
[Edited on 17-2-2016 by deltaH]
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zed
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Amide? Maybe. There is a certain possibility of aziridine type formation via dehydration.
A purported possible intermediate in the HI/P reduction of ephedrine , is a three membered ring, with the amino function Bridging the Alpha and Beta
carbons.
So, how much heat?
Enough heat and pressure, may result in the amino function being
alkylated by the alcohol.
Amides may also be alkylated by this method.
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byko3y
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You can produce one, or another, or mixture of products depending on conditions and reagents.
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deltaH
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My compounds are not volatile, so I'm heating to 150°C for about an hour in my initial experiments.
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